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Abstract Teapot Dome oilfield near the town of Midwest, Wyoming, has been the testing site of numerous drilling and production techniques since the early 1900's. The structure is a doubly plunging basement-cored anticline that formed during the Laramide orogeny, with sediments ranging from Cambrian to Quaternary. The Steele, Niobrara, and Mowry formations are potential source rocks in the area. In this study, we combine geochemical analyses with one-dimensional modeling of burial history, thermal maturity, and timing of petroleum generation to evaluate the potential of the field for unconventional exploration. Rock Eval™ pyrolysis and oxidation results show a mixture of Type II and Type III kerogen in the Niobrara and Mowry formations, and no hydrocarbon generation potential for the Steele Formation. These geochemical results, combined with regional tectonics, stratigraphy, and sedimentological conditions, were implemented into burial history and maturation models. Results from the modeling show that the Niobrara and Mowry formations are in the early oil generation window. The Mowry is the most mature of the three formations, but only 10% of the kerogen has been converted to oil. The study area did not reach the thermal maturity required to generate the significant amount of oil and gas produced to date from the structure. The results and method of this study can easily be extrapolated to better constrain the basin evolution of nearby fields. This study is significant for further exploration in other established Laramide basins with similar formations. Highlights • This study combines hydrocarbon source rock characterization, burial history and thermal maturity basin modeling. • Results reveal that only a small amount of hydrocarbons is being or has been generated in situ at Teapot Dome. • Rock Eval analyses show that the Steele has no potential, the Niobrara and Mowry are in very early oil generation window. • Mowry is the most mature of the three formations but we estimate that only 10% of the kerogen has been converted to oil. • The investigated units did not reach thermal maturity required to generate the amount of oil and gas produced. [ABSTRACT FROM AUTHOR]

Objective: The study of health-related care provision in archeology gives important indications on the culture and community organization of past populations. This study aims to assess the health status of the skeletal assemblage recovered from the burial site of St. Biagio (Ravenna, 17th-18th Centuries); next, we identified likely instances of need for and receipt of caregiving in response to the condition, to examine evidence of community attitudes toward disease and disability., Materials and Methods: The skeletal assemblage is composed of 133 individuals in a generally good state of preservation. Sex and age-at-death were estimated through classical anthropological methods. Health status was inferred through the biological index of frailty (BIF) and paleopathological analysis was performed through macroscopic and radiographic investigations. The "bioarcheology of care" approach was applied to individuals who showed evidence of impairment and disability., Results: The skeletal assemblage of St. Biagio was equally represented by males and females (50% males), with a higher percentage of adults (83.4%) than subadults (10.5%), and this is reflected in the high life expectancy at birth (40.3 years). No significant differences in health status emerged between age groups and sexes, with a generally high percentage of joint diseases, antemortem trauma, and infectious diseases. Evidence of care and compassion was found in some individuals with a high degree of impairment or disability, as in the case of probable Angelman syndrome., Discussion: This study provided important insights into the biological and social aspects of an Early Modern population in Northern Italy, showing that people with functional and/or visible abnormalities were probably cared for in life and were presumably considered full members of the society., (© 2023 The Authors. American Journal of Biological Anthropology published by Wiley Periodicals LLC.)

The fear of being buried alive or taphophobia remains a significant concern for a number of individuals. In previous centuries however, reports of live burials were frequently promulgated in the media fostering an industry focused around the manufacturing and selling of security coffins which either facilitated egress or enabled the recently buried to alert those on the surface to their plight. Holding mortuaries with resuscitation facilities were also established mainly in Continental Europe to permit close observation of the recently deceased until definitive signs of putrefaction had developed. Underpinning much of this panic was the inability of medical practitioners to definitely diagnose death. Although still a rare possibility, mainly in situations where qualified medical personnel are not available, the likelihood of alive burial is nowadays fortunately rare., (© 2023. The Author(s).)

Abstract The palyno-organic facies aspects of the subsurface Lower Cretaceous core samples are extensively investigated in three wells in the northern part of the Western Desert of Egypt. These wells are Burg El Arab-1 and Mamura-1, Mersa Matruh-1 (BAX-1, MAX-1 and MMX-1 respectively). The study is based on the palynofacies and organic geochemical analyses. The palynofacies examination includes a statistical analysis of the different classes of organic particles by cluster analysis and principal component analysis (PCA). This analysis leads to identify 4 palynofacies types (A, B, C 1 and C 2) which are dominated by various levels of terrestrial floral materials. The paleoenvironmental settings that are attributed to these palynofacies types are the distal suboxic-oxic, proximal oxic, transitional oxic and highly distal oxic. The principal component analysis (PCA) differentiates between these palynofacies types mathematically by the biplot of components 1 and 2. The component 1 corresponds to distance from the terrestrial floral sources. The identification of quantity, type, quality and thermal maturity of organic matter is discussed depending on the palynofacies and organic geochemical analyses. The thermal maturity is assessed digitally by measuring the RGB color channels in the spore images and their corresponding thermal alteration index (TAI incorporated with values of T max). These measures are integrated in burial history models with geothermal gradient and depositional history. The study reveals that most of the core samples represent generally fair to good enriched sources of gas prone type III kerogen and less mixed gas-oil type II/III kerogen. Additionally, some occasional high levels of organic conversions are recorded. The burial history models indicate that oil expulsion window initiated in the Cretaceous. The examinations indicate mature oil sources in the Alam El Bueib Formation in MMX-1 well. The organic geochemical parameters are correlated versus the component 1 and sum of all components of PCA. The correlation coefficients (R2) pointed to good correlation between the oxygen index (OI), TOC and S 2 and lower correlation with hydrogen index (HI). Highlights • A comprehensive palyno-organo facies analysis for the core samples from the subsurface Lower Cretaceous. • Four palynofacies types were identified each represent a specific paleoenvironmental setting. • Geochemical analysis reveals fair to good sources with gas prone type III and less mixed gas-oil type II/III kerogens. • The examinations indicate mature oil sources in the Alam El Bueib Formation in MMX-1 well. [ABSTRACT FROM AUTHOR]

Copyright of Oil Drilling & Production Technology / Shiyou Zuancai Gongyi is the property of Shiyou Zuancai Gongyi Bianjibu and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract During the interaction between the South China plate and the North China plate, the southern North China Basin (SNCB) underwent a strong tectonic thermal evolution in the early Mesozoic. Recently, burial history reconstruction and thermal maturity simulation of coal-bearing strata from the Late Carboniferous to the present were carried out in the SNCB. Rock-Eval pyrolysis (12 samples), vitrinite reflectance (60 samples), apatite fission track (AFT) analysis (17 samples), and PetroMod 1D were performed on wells located in the SNCB. Geothermal gradients were found to range between 30.3 and 36.4 °C/km, averaging 31.0 °C/km, and present heat flow was found to vary between 51 and 58, averaging 55 mW/m2. The paleo heat flow model with higher heat flow peaks of 86 mW/m2 during the first rifting phase resulted in the best fit between the calculated and the observed vitrinite reflectance and bottom hole temperatures in the modeling. Using this model of thermal maturity history combined with AFT analysis, we analyze the main hydrocarbon generation stages and discuss the coupling relationship of thermal maturity history with tectonic evolution. The results indicate that tectonic activities restrict the thermal maturity evolution of source rocks to a large extent by controlling the geotemperature. The thermal history demonstrates that two phases of heating (315–163 Ma, 83–38 Ma, depositing) happened to the source rocks, separated by two cooling (163–83 Ma, 38–23 Ma, uplifting) events. The maturity history indicates that the process of hydrocarbon generation can be divided into three stages in the SNCB (315–163 Ma, thermal genesis gas generation stage; 163–83 Ma, gas reservoir destruction stage; 83–0 Ma, secondary biogas generation stage). Hydrocarbon generation started as early as 198 Ma with a peak at 162 Ma, and expulsion started at around 195 Ma. The Taiyuan and Shanxi formations' source rocks reached a high maturity (1.0% < R o < 1.3%) with a greater potential for hydrocarbon generation, and the Xiashihezi formation is mid-mature (0.7% < R o < 1.0%) with limited hydrocarbon generation potential at the present day. Highlights • Geothermal gradients were found to range between 30.3 and 36.4 °C/km, averaging 31.0 °C/km, and present heat flow was found to vary between 51 and 58, averaging 55 mW/m2. Paleo heat flow model with higher heat flow peaks of 86 mW/m2 during the first rifting phase. • The thermal history demonstrates that two phases of heating (depositing) happened to source rocks, separated by two cooling (uplifting) events. • The thermal maturity history indicated that the process of hydrocarbon generation can be divided into three stages in the SNCB, orogenesis restrict the thermal maturity evolution of source rocks to a large extent. [ABSTRACT FROM AUTHOR]

The Huanghua Depression is located in the north-centre of Bohai Bay Basin, which is a rift basin developed in the Mesozoic over the basement of the Huabei Platform, China. Permo-Carboniferous source rocks were formed in the Huanghua Depression, which has experienced multiple complicated tectonic alterations with inhomogeneous uplift, deformation, buried depth and magma effect. As a result, the hydrocarbon generation evolution of Permo-Carboniferous source rocks was characterized by discontinuity and grading. On the basis of a detailed study on tectonic-burial history, the paper worked on the burial history, heating history and hydrocarbon generation history of Permo-Carboniferous source rocks in the Huanghua Depression combined with apatite fission track testing and fluid inclusion analyses using the EASY%Ro numerical simulation. The results revealed that their maturity evolved in stages with multiple hydrocarbon generations. In this paper, we clarified the tectonic episode, the strength of hydrocarbon generation and the time–spatial distribution of hydrocarbon regeneration. Finally, an important conclusion was made that the hydrocarbon regeneration of Permo-Carboniferous source rocks occurred in the Late Cenozoic and the subordinate depressions were brought forward as advantage zones for the depth exploration of Permo-Carboniferous oil and gas in the middle-northern part of the Huanghua Depression, Bohai Bay Basin, China. [ABSTRACT FROM AUTHOR]

The oil, gas and condensate province of the Upper Cretaceous to Cenozoic Taranaki Basin is very important as it has become the sole commercially-producing sedimentary basin in New Zealand. An understanding of burial/thermal geo-histories of Taranaki Basin is essential for modeling hydrocarbon generation. In the present study, data from subsurface samples from selected wells have been analyzed and interpreted for characterizing source rock of the Pakawau Group along with thermal geohistory of the basin. The Upper Cretaceous Pakawau Group, made up of Rakopi (87-75 Ma) and North Cape (75-65 Ma) formations, is the eldest and most prolific organic rich hydrocarbon source rock in the basin. Their lithologies vary between carbonaceous mudstone and coal from alluvial to coastal plain depositional environments with marginal marine influence. Most samples that are interpreted contain kerogen Types II and II-III, with few samples of Type-III kerogen. This is validated by the biomarkers results, where the assessed data shows that the organic source ranges from terrestrial to marine origin. The Pakawau Group source is immature to mature, as reflected by the distribution of vitrinite reflectance (%Ro), pyrolysis T max from pyrolysis data and biomarkers data. Vitrinite reflectance distribution shows that the Rakopi Formation is mostly within the mature oil window for hydrocarbon generation with values ranging generally between 0.5% and 0.95% Ro. Using two selected wells, the models have been interpreted to generate hydrocarbons from the Pakawau Group between Upper Paleocene and Middle Eocene. Interpretations of the burial models confirm that hydrocarbons of Pakawau Group has not yet attained peak generation and is still being expelled from the source rock to-date. [ABSTRACT FROM AUTHOR]

The Hoiho Formation in the Great South Basin (GSB) of New Zealand has been analysed for source rock characterization, hydrocarbon generation modelling, and interpretation of paleodepositional environment. Rock-Eval pyrolysis results from wells indicate the presence of excellent organic matter quality and quantity. The Hoiho Formation is dominantly of kerogen type II-III (oil and gas prone) and kerogen type III (gas prone). High values are also recorded for total organic carbon (TOC), hydrocarbon volume generated during pyrolysis (S2) and hydrogen index (HI). Based on the maximum pyrolysis temperature and vitrinite reflectance values in Kawau-1A, Toroa-1 Tara-1 wells, it can be concluded that the Hoiho Formation is thermally mature only at the Central Graben of the basin, where these three wells are positioned at. Conversely, thermally immature source rock of the Hoiho Formation is recorded in the Hoiho-1C well. Important biomarkers and their derivatives, such as regular steranes, Pristane and Phytane confirm that Hoiho source rock was originally from a terrestrial source. Onedimensional basin modelling was applied to reconstruct the burial and thermal maturity histories of the formation. The top of oil window was reached at approximately 29 Ma, 53 Ma and 57 Ma at Kawau-1A, Toroa-1 and Tara-1 wells respectively. [ABSTRACT FROM AUTHOR]

The Ediacaran (Upper Neoproterozoic) succession in west and SW Ukraine and Moldova rests on a Cryogenian succession or basement. The succession is exposed at the surface along the southern margin of the Ukrainian Shield and dips to the SW towards the Carpathian Overthrust; where burial depths are sufficient, it is mature for oil and gas generation. The Ediacaran succession is made up of terrigenous siliciclastics ranging from conglomerates and sandstones to siltstones and mudstones, and includes a shale interval (the Kalus Beds) which may have source rock potential. Organic matter in the Kalus shales includes Vendotenides sp. (colonial bacteria) together with amorphous OM. This paper presents a study of the Kalus Beds and is based on data from surface and core samples and thin sections, and the results of Rock-Eval pyrolysis and reflectance analyses. TOC contents in the Kalus shales are in general <0.5 wt%, although the measured TOC was 0.89 wt% and 0.84 wt%, respectively, in samples from the Sokal-1 borehole and the Mynkivtsi outcrop location in SW Ukraine. The low present-day TOC in borehole samples may be due to the thermal transformation of the OM originally present. Reflectivity as measured on vitrinite-like macerals and bitumen in samples from outcrops ranges from 0.63 to 1.28% VRoeq indicating a relatively low level of thermal maturity. However, the generally low TOC values in the outcrop samples mean that the Kalus Beds in general have little hydrocarbon potential in the study area. The burial and thermal history of the Ediacaran succession in SW Ukraine and the Moldovian Platform was reconstructed, and 1D modelling was carried out at the Brody-1, Chernivtsi-1, Dobrotvir-1, Kolynkiv-1, Litovyzh-1, Ludyn-1, Lyman-1, Peremyshlyany-1, Sokal-1 and Voyutyn-1 boreholes. The results of modelling indicate that maturities equivalent to the onset of the oil window were reached from the Early Devonian through the Early Carboniferous. Slightly higher modelled maturities occurred in boreholes located near the Teisseyre-Tornquist Zone. The modelled transformation ratio for kerogen in the Kalus Beds is high and may exceed 90% in the boreholes studied. [ABSTRACT FROM AUTHOR]

The successful exploration and production of shale-gas resources in the United States and Canada sets a new possible solution towards the energy crisis presently affecting most countries of Asia. This study focuses on the use of well log and 2D seismic data for the characterization of the shale oil/gas potential of a Paleocene-Eocene succession - the Meyal area in the Potwar Basin of Pakistan. Two shaly plays are identified in Paleocene-Eocene strata in well logs using Δ Log R and modified Δ Log R cross-plot techniques. The results indicate that Paleocene shale (the Patala Formation) and the lower shaly part of Eocene limestone (Sakesar Formation) can be potentially mature source rocks. However, the thermal maturity modelling proves that only the Paleocene shale is mature. Our results also suggest that the maturity responses on Δ Log R models for the lower shaly part of the Eocene limestone are due to trapped hydrocarbons in the intra-formational fractures. Petroelastic/petrophysical analysis of the Patala Formation reveals two potential shale oil/gas zones on the basis of Young's modulus, Poisson's ratio, Brittleness index and Total Organic Content at an exploitation depth of 3980-3988 m. This work can provide valuable insight for estimating shale oil/gas potential in highly deformed basins not only in Asia but in other parts of the world. [ABSTRACT FROM AUTHOR]

In order to accurately reconstruct the burial and thermal history of sedimentary basins, one of the key uncertainty that should be addressed is the accurate delineation of the maximum burial depths and estimation of the thickness of eroded sections in the basin. Several methods have been routinely utilized to account for this, but each with its limitations. Here, we have utilized the sonic transit time data to account for the amounts of removed sections in the Broome Platform of the partly exhumed Canning Basin, Western Australia. The observed exhumed values are further compared with the values from AFTA (Apaptite Fission Track Analysis) data as well as results of exhumation observed from the projection of vitrinite reflectance data. Furthermore, a mathematical relationship is established between the amounts of exhumation and the sonic transit time (DT) and depth. The results from the calculated exhumed sections show a good correlation with the estimated removed sections reported from AFTA but poor correlations with the projected vitrinite reflectance profiles. While AFTA and vitrinite reflectance methods are widely used in the industry, the exhumation estimates derived from sonic-porosity logs are usually independent of the thermal history of the basin and thereby would provide more accurate inputs or further constraints into the burial history model. Also, in this study, the results from the AFTA usually allows for a wide range of uncertainty, while the calculation of exhumation values from the new approach gives an absolute exhumation value for the well locations. Furthermore, the sonic log approach has been able to identify and estimate the magnitude of an older erosional event that was not previously reported in the Geotrack report based on thermal history methods. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the Japanese Association for Petroleum Technology is the property of Japanese Association for Petroleum Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Following the publication (Granger DE et al., Nature 2015;522:85-88) of an 26Al/10Be burial isochron age of 3.67±0.16 Ma for the sediments encasing hominin fossil StW573 ('Little Foot'), we consider data on chert samples presented in that publication to explore alternative age interpretations. 10Be and 26Al concentrations determined on individual chert fragments within the sediments were calculated back in time, and data from one of these fragments point to a maximum age of 2.8 Ma for the sediment package and therefore also for the fossil. An alternative hypothesis is explored, which involves re-deposition and mixing of sediment that had previously collected over time in an upper chamber, which has since been eroded. We show that it is possible for such a scenario to yield ultimately an isochron indicating an apparent age much older than the depositional age of the sediments around the fossil. A possible scenario for deposition of StW573 in Member 2 would involve the formation of an opening between the Silberberg Grotto and an upper chamber. Not only could such an opening have acted as a death trap, but it could also have disturbed the sedimentological balance in the cave, allowing unconsolidated sediment to be washed into the Silberberg Grotto. This two-staged burial model would thus allow a younger age for the fossil, consistent with the sedimentology of the deposit. This alternative age is also not in contradiction to available faunal and palaeomagnetic data. [ABSTRACT FROM AUTHOR]

Based on previous research examining the controlling factors of the generation and decomposition of organic acids, our study discusses the effect of burial processes on the evolution of organic acids and the development of secondary pores related to acidic dissolution using a case study of the Nanpu Sag, Bohai Bay Basin, China. The depth range of the present distribution of organic acids was determined from the measured data for vitrinite reflectance (R o ) and formation temperature to be approximately 2000–3500 m. This range corresponds to the vertical distribution of feldspar dissolution pores, except for the No. 3 structural belt, a risk exploration area, where feldspar dissolution can be observed in a deeper interval corresponding to the Es 1 Formation. This finding indicates that feldspar was dissolved in the early burial stage of the Es 1 Formation of the No. 3 structural belt, unlike in the other structural belts. During the Shahejie depositional period, the subsidence rate was lower than it was during the Dongying depositional period, except at the No. 3 structural belt. The subsidence rate at the No. 3 structural belt was higher during the Shahejie depositional period because this structural belt is adjacent to the east section of the Shabei Fault. Simulations of the organic matter evolution for two types of burial history were processed to clarify the effect of burial history on organic acids evolution. Consequently, we suggest that the different burial histories result in different situations of secondary pore development. A slow-to-fast process leads to delayed generation of organic acids and high formation temperature, which results in the decomposition of organic acids, and hence weakened dissolution. Conversely, a fast-to-slow process preserves organic acids well and strengthens dissolution in the early burial stage. [ABSTRACT FROM AUTHOR]

The Sheepbed mudstone forms the base of the strata examined by the Curiosity rover in Gale Crater on Mars, and is the first bona fide mudstone known on another planet. From images and associated data, this contribution proposes a holistic interpretation of depositional regime, diagenesis and burial history. A lake basin probably received sediment pulses from alluvial fans. Bed cross-sections show millimetre to centimetre-scale layering due to distal pulses of fluvial sediment injections (fine-grained hyperpycnites), fall-out from river plumes, and some aeolian supply. Diagenetic features include mineralized synaeresis cracks and millimetre-scale nodules, as well as stratiform cementation. Clay minerals were initially considered due to in situ alteration, but bulk rock chemistry and mineralogy suggests that sediments were derived from variably weathered source rocks that probably contained pre-existing clay minerals. X-ray diffraction analyses show contrasting clay mineralogy in closely spaced samples, consistent with at least partial detrital supply of clay minerals. A significant ( ca 30 wt%) amorphous component is consistent with little post-depositional alteration. Theoretical modelling of diagenetic reactions, as well as kinetic considerations, suggest that the bulk of diagenetic clay mineral formation occurred comparatively late in diagenesis. Diagenetic features (synaeresis cracks and nodules) were previously thought to reflect early diagenetic gas formation, but an alternative scenario of synaeresis crack formation via fabric collapse of flocculated clays appears more likely. The observed diagenetic features, such as solid nodules, hollow nodules, matrix cement and 'raised ridges' (synaeresis cracks) can be explained with progressive alteration of olivine/glass in conjunction with centrifugal and counter diffusion of reactive species. Anhydrite-filled fractures in the Sheepbed mudstone occurred late in diagenesis when fluid pressures built up to exceed lithostatic pressure. Generating fluid overpressure by burial to facilitate hydraulic fracturing suggests a burial depth of at least 1000 m for the underlying strata that supplied these fluids. [ABSTRACT FROM AUTHOR]

Paleozoic sedimentary succession research is valuable for better understanding the global petroleum province and future hydrocarbon reserves. Paleozoic rocks are the prime source of the enormous hydrocarbon fields in North Africa. Despite the Western Desert of Egypt being part of the North African Platforms and having similar depositional, tectonic, and diagenetic constraints, the hydrocarbon system for Paleozoic rocks in the Siwa Basin is indeed not characterized. Forty-five Paleozoic samples were collected from the Siwa Basin to evaluate the source rock characteristics using Rock-Eval pyrolysis, vitrinite reflectance, stable carbon isotopes, biomarkers, headspace gas, and palynofacies analyses. Additionally, the burial and thermal histories of these rocks were investigated by 1D basin modeling. The Paleozoic succession is represented by the Silurian (Basur Formation), Devonian (Zeitoun and Desouqy formations), and Carboniferous (Dhiffah Formation). The routine bulk geochemical analysis of the studied samples indicates poor to good source rock potential. The studied samples contain mostly kerogen type III with some kerogen type II, whereas the Carboniferous samples contain mostly kerogen type IV. The organic matter of the Devonian samples is suggested to have originated from marine and terrigenous sources, with a dominant upward terrigenous source. The lower part of the Devonian is deposited in more reduced marine conditions than the upper part. The organic matter is found to be mature, as indicated by Rr%, T max , and biomarker data. The composition of collected headspace gases in Paleozoic rocks suggests their thermogenic origin. Moreover, the similarity of the molecular composition between Paleozoic source rocks and crude oil in reservoir rocks supports the same hydrocarbon sources. Accordingly, the petroleum system in the Siwa Basin is based on active Paleozoic source rocks that charge and accumulate hydrocarbons in the sand reservoirs of the Desouqy Formation. The Paleozoic section entered the oil window in the Early Cretaceous (∼101 myr) based on its burial history. Thus, this study gives improved insights into the petroleum system in the Siwa Basin. Additionally, the Siwa Basin's lesser thickness and burial depth in comparison to other North African basins most likely contributed to its poor petroleum potential. • Paleozoic rocks have poor to good source rock potential. • Organic matter is derived from marine and terrigenous sources. • Source rocks were deposited in a reducing environment. • Paleozoic rocks in Siwa Basin have active source rocks. [ABSTRACT FROM AUTHOR]

Amorium is a Byzantine city located in the province of Afyonkarahisar, Turkey. Excavations in the 2007, 2008 and 2009 seasons yielded many tombs containing non-adults, mostly infant burials, located to the north of the Lower City Church while the south of the Church was reserved for family and adult tombs. Among the excavated trenches A20 is the largest area and located immediately to the east of the baptistery, other trenches in the Lower City Church (A17, A19, A22, A35, A36, and A38) are located further away from the baptistery and consist of smaller rooms. Skeletal remains of 280 individuals from these trenches dating to 10 th to 11 th centuries AD were analysed in order to find out if there are any indications for differences in their social status, preferential choices for the burial places, or age-related distribution of the burials of the non-adults in the North Cemetery. This study, together with the baptism traditions and social hierarchy of the Mid-Byzantine era, tentatively suggests that the A20 area might have been reserved for children of families of higher rank in society as it was the closest area to the baptistery (presumably some of the infants had not lived long enough to be baptised), whereas infants and some older children of lower rank in the society were buried in outlying areas. Hence, this study attempts to offer a new insight into burial practices in mid-Byzantine Amorium.

The excavation of skeletal human remains from St. Dionysius in Bremerhaven-Wulsdorf showed a strong association between infant burials and their location in and around the church. Accumulations of young children close to a church and its corners are repeatedly reported and are commonly defined as "eaves-drip" burials. Although there are no early medieval written sources for this specific burial practice, the proximity of the graves of small children to the sites of early Christian churches is noticeable. Above all, the temporal context plays an important role in the interpretation of these burials, since it is questionable whether the intention to baptise the graves with rainwater from the eaves was the same for the Early Middle Ages as it was for the High and Post Middle Ages. The frequently observed relationship between locality and infant bones must not be regarded as an ordinary burial since the choice of burial place already indicates a special position within the graveyard. Particularly regarding the progress of Christianisation and thus the assertion of the Christian belief system in the early phases, it is essential to reflect on the people's real acceptance of Christian religious practices and rituals. It is therefore crucial to consider the circumstances and belief systems of the particular era before associating eaves-drip burials with the unbaptised child.

Social anthropology and ethnographic studies have described kinship systems and networks of contact and exchange in extant populations 1-4 . However, for prehistoric societies, these systems can be studied only indirectly from biological and cultural remains. Stable isotope data, sex and age at death can provide insights into the demographic structure of a burial community and identify local versus non-local childhood signatures, archaeogenetic data can reconstruct the biological relationships between individuals, which enables the reconstruction of pedigrees, and combined evidence informs on kinship practices and residence patterns in prehistoric societies. Here we report ancient DNA, strontium isotope and contextual data from more than 100 individuals from the site Gurgy 'les Noisats' (France), dated to the western European Neolithic around 4850-4500 BC. We find that this burial community was genetically connected by two main pedigrees, spanning seven generations, that were patrilocal and patrilineal, with evidence for female exogamy and exchange with genetically close neighbouring groups. The microdemographic structure of individuals linked and unlinked to the pedigrees reveals additional information about the social structure, living conditions and site occupation. The absence of half-siblings and the high number of adult full siblings suggest that there were stable health conditions and a supportive social network, facilitating high fertility and low mortality 5 . Age-structure differences and strontium isotope results by generation indicate that the site was used for just a few decades, providing new insights into shifting sedentary farming practices during the European Neolithic., (© 2023. The Author(s).)

Rock physics permits the integration of geophysical and geological information. The incorporation of geology information assists in constraining non-uniqueness during quantitative interpretation. In this investigation, Kanywataba well was first analyzed qualitatively by use of cross plots to ascertain whether the various logs (P-wave velocity versus S-wave velocity, density versus porosity) conform to conventional trends. It was observed that density decreases with porosity and the cross plot of P-wave velocity versus S-wave velocity indicates an increasing trend of the two parameters. Rock physics models were applied to delineate reservoir properties with reference to Kanywataba-1 well of the Semliki basin in the Albertine graben. The two rock physics models namely; the patchy constant cemented model and the constant cement model described the Upper Pliocene Formation and Upper Miocene Formation respectively. The analysis revealed high sandstone bulk modulus values are attributed to the presence of feldspars, micas, and calcareous clays in the reservoir units. The data interpretation was executed using rock physics templates that provide a quantitative interpretation of reservoir properties based on the area's local geology. The rock physics templates of Vp/Vs ratio versus acoustic impedance indicate 5%gas for Upper Miocene Formation and 50% gas for Upper Pliocene Formation. In both Formations, three lithological zones interpreted as gas sand, brine sand, and shaly sand were observed. With information from the burial history of the sediments within the Albertine Graben and constant cement model, compaction regime were observed. The Upper Miocene Formation indicates the presence of a chemical compaction regime which implies, that it has undergone diagenesis with evidence from logs indicating higher velocities, lower porosity, and some amount of cementation associated with this Formation. • The study provided the link between geophysical parameters and geological aspects by using rock physics analysis. The study generated two rock physics models namely; the patchy cement model and the constant cement model through rock physics modeling. • Quantitative analysis of the different reservoir properties; lithology, porosity, and fluid saturation of the area aided by rock physics templates. The study utilized rock physics templates of Vp/Vs ratio versus acoustic impedance. • The study explored the use of rock physic modelling with burial history of the area. The Upper Miocene Formation indicated the presence of chemical compaction regime. [ABSTRACT FROM AUTHOR]

Multidisciplinary research on human remains can provide important information about population dynamics, culture diffusion, as well as social organization and customs in history. In this study, multidisciplinary analyses were undertaken on a joint burial (M56) in the Shuangzhao cemetery of the Tang Dynasty (618-907 AD), one of the most prosperous dynasties in Chinese history, to shed light on the genetic profile and sociocultural aspects of this dynasty. The archaeological investigation suggested that this burial belonged to the Mid-Tang period and was used by common civilians. The osteological analysis identified the sex, age, and health status of the three individuals excavated from M56, who shared a similar diet inferred from the stable isotopic data. Genomic evidence revealed that these co-buried individuals had no genetic kinship but all belonged to the gene pool of the ancient populations in the Central Plains, represented by Yangshao and Longshan individuals, etc. Multiple lines of evidence, including archaeology, historic records, as well as chemical and genetic analyses, have indicated a very probable familial joint burial of husband and wives. Our study provides insights into the burial customs and social organization of the Tang Dynasty and reconstructs a scenario of civilian life in historic China., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Zhao et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

As the exploration of hydrocarbons moves into more complex and deeper basinal settings the need to understand the effect of high temperatures and high pressures on reservoir quality and rock properties becomes even more important. The fluvial channel sandstone reservoirs of the Skagerrak Formation in the Central North Sea exhibit anomalously high porosities and permeabilities considering their depth of burial (>3500 m below sea floor). Despite the complex depositional setting, diagenetic history, high overpressure and temperatures encountered in the Skagerrak Formation, hydrocarbons are currently being produced. The Skagerrak Formation reservoirs used in this study have encountered overpressures of >40 MPa and temperatures up to ∼185 °C at present day maximum burial. To identify the role played by the high pressure and high temperature encountered in the reservoir sandstones a multidisciplinary approach involving petrographic, fluid inclusion, and burial history modelling studies has been adopted. Our interpretation of the results is that the generation of shallow overpressure in these fields limited mechanical compaction and also played an important role in minimizing pressure solution in the chemical compaction regime as evidenced by reduced quartz cementation. Fluid inclusions found in the quartz overgrowths indicate late-stage development with temperatures of formation in the range 130 to 170 °C coincident with late-stage deeper burial. Hydrocarbon emplacement occurred after quartz cementation and has had little to no effect on porosity preservation. The formation of well-developed authigenic chlorite (>70% surface coating) and, to a lesser extent illite clay coats with burial had a positive effect on porosity preservation even though permeability was marginally reduced in the illite-rich sandstones. A schematic porosity and quartz cement evolution model has been developed which allows for pre-drill prediction of reservoir quality in the Heron Cluster and provide valuable insights for other complex high-pressure high-temperature reservoirs. [ABSTRACT FROM AUTHOR]

The Natih B source rock of the Jebel Akhdar dome in the Oman Mountains hosts at least three different generations of solid bitumen. This study presents detailed analyses of thermal maturity based on solid bitumen reflectance, Rock-Eval pyrolysis, Fourier transform infrared spectroscopy and Raman spectroscopy of matrix and solid bitumen. The Natih B source rock was sampled in different valleys (Wadis) around the Jebel Akhdar dome. Detailed petrography of organic material was conducted by optical and scanning electron microscopy (SEM). The petrographic data was used to calibrate an integrated thermal basin model of the Wadi Nakhr area. Due to ophiolite obduction the Natih B source rock was buried to 7.4 to 8 km and a maximum temperature of c. 240 °C. Hydrocarbon generation and associated primary migration was burial induced and took place from 78 to 66 Ma with solid bitumen precipitation in the source rock. A resulting high-reflective solid bitumen generation reflects temperatures of deepest burial in the order of 225 °C to 240 °C. Based on an elaborated paragenetic sequence two other solid bitumen generations were linked to two oil migration events taking place during uplift (55–50 Ma and 48–45 Ma), after deepest burial (around 65 Ma). [ABSTRACT FROM AUTHOR]

The Ahvaz anticline which is located in the middle region of the Dezful Embayment is certainly one of the most important oilfields in Iran. Burial history reconstruction and one-dimensional thermal maturity modeling of the Late Jurassic to Present-day successions have been conducted in the Ahvaz anticline. The petroleum generation bulk kinetic parameters of the Kazhdumi and Pabdeh formations were computed by a non-isothermal open system pyrolysis at different heating rates. Bulk kinetic experiments reveal that a relatively narrow distribution of activation energies, range from 40 to 52 kcal/mol for the Kazhdumi samples and from 42 to 54 kcal/mol for Pabdeh shales, are directly related to the homogeneity in the organic matter. The principal activation energies of 46 kcal/mol and 48 kcal/mol, frequency factors of 4.36×10 +11 s −1 and 1.91×10 +12 s −1 and hydrogen indexes (HI) of 123 and 351 mg/g TOC have been computed for the Kazhdumi and Pabdeh formations, respectively. The lithology composition (percentages of shale, marl, gypsum, limestone and sandstone) of the Late Jurassic-Present formations in the selected wells was determined by using cutting samples and wireline well log data. The computed kinetic parameters and derived lithology composition of strata were applied to thermal maturity modeling. Thermal maturity modeling and burial history reconstruction which is calibrated by vitrinite reflectance data and formation temperature indicate that the palaeo-heat flow ranges from 37 mW/m 2 to 41 mW/m 2 . The Kazhdumi Formation entered the main stage of oil generation during the Late Miocene (6.5 Ma) and the Pabdeh Formation reached early stage of oil window from the Early Pliocene (3.5 Ma). Our results provide the bulk petroleum generation kinetic parameters description of the Kazhdumi and Pabdeh formations and demonstrate the thermal maturation state of source rocks, especially the Albian shales, that has been recognized as most important source rock in the Dezful Embayment. [ABSTRACT FROM AUTHOR]

The Sufyan Depression is located in the northwest of Muglad Basin and is considered as a favorable exploration area by both previous studies and present oil shows. In this study, 16 wells are used or referred, the burial history model was built with new seismic, logging and well data, and the thermal maturity (Ro, %) of proved AG source rocks was predicted based on heat flow calculation and EASY %Ro modeling. The results show that the present heat flow range is 36 mW/m 2 ∼50 mW/m 2 (average 39 mW/m 2 ) in 13 wells and 15 mW/m 2 ∼55 mW/m 2 in the whole depression. Accordingly, the geothermal gradient is 20 °C/km∼26 °C/km and 12 °C/km∼30 °C/km, respectively. The paleo-heat flow has three peaks, namely AG-3 period, lower Bentiu period and Early Paleogene, with the value decreases from the first to the last, which is corresponding to the tectonic evolution history. Corresponding to the heat flow distribution feature, the AG source rocks become mature earlier and have higher present marurity in the south area. For AG-2_down and AG-3_up source rocks that are proved to be good-excellent, most of them are mature with Ro as 0.5%–1.1%. But they can only generate plentiful oil and gas to charge reservoirs in the middle and south areas where their Ro is within 0.7%–1.1%, which is consistent with the present oil shows. Besides, the oil shows from AG-2_down reservoir in the middle area of the Sufyan Depression are believed to be contributed by the underlying AG-3_up source rock or the source rocks in the south area. [ABSTRACT FROM AUTHOR]

Burial and thermal histories of Wufeng-Longmaxi shale (O3w-S1l) in Jiaoshiba, an important shale gas exploration target in SE Sichuan, were modeled using PetroMod software. Results of Well JY4 show the shale was buried to 2000 m in Silurian, uplifted 1000 m due to a later erosion, subsided again at Permian, and reburied to maximum depth around 6200 m at the end of Cretaceous (K3). Finally, the shale uplifted to the current depth of 2500 m. Thermal history of the shale was reconstructed based on the burial evolution after constrained by measurements. The shale entered oil-window in later Silurian and passed gas generation peak at early Triassic. Thermal maturation accelerated significantly since the Triassic and finalized its maximum maturation (2.0–2.5% Ro) at K3. [ABSTRACT FROM AUTHOR]

The Cenozoic evolution of the Barents Sea has been widely debated for its implications on hydrocarbon exploration. In this paper, we provide the first, for the area, apatite (U–Th)/He thermochronology data on Early-Middle Jurassic and Early Cretaceous sandstone reservoir samples obtained from three wells located on the western part of the Barents Shelf. A large range of grain ages have been detected, ranging from 1.58 to 50.65 Ma. These thermochronological data, initially integrated with vitrinite reflectance measurements to properly constrain the burial history evolution, have been modelled on the basis of estimated maximum temperature in order to evaluate the cooling path to present-day temperatures. Outputs from modelling indicate that: 1) the amount of net uplift and denudation is in the order of 1000 m, and 2) the last important phase of exhumation occurred during late Miocene-early Pliocene time, therefore challenging the prevailing idea of substantial uplift linked to the observed shelf-progradation along the margin as a result of the Plio-Pleistocene glaciations. The timing of the distinct exhumation event documented here may be, instead, attributed to different mechanisms. These may include basin inversion widespread on the NW European margin that is probably related to local changes in the North Atlantic spreading vector, while other mechanisms may include thermal and lithospheric-scale anomalies observed at the northwestern corner of the Barents-Svalbard Shelf. [ABSTRACT FROM AUTHOR]

This study evaluates the hydrocarbon generation potentials and time of generation for Paleocene to Lower Miocene source rock horizons from A-1, B-1, B-2, and C-1 wells in the Niger Delta Basin using 1D Petromod modeling software. Wells A-1, B-1 and B-2, and C-1 are located within the Central Swamp, the Coastal Swamp, and the Shallow Offshore depobelts, respectively. The thermal history was derived from the rifting-subsidence heat flow model. Maturity modeling were carried out by using Easy%Ro kinetic model and a heat flow history predicting present-day heat flow which were calibrated with measured temperature data. Results of the study suggest that these potential source rocks have attained maturity status to generate hydrocarbons, with vast differences existing in the timing of the onset of oil generation. Basin modeling suggests that Paleocene source rocks entered the oil generative window from the Oligocene to Miocene times with thermal maturity window that varies from gas generation to early-mature phase. The Eocene source rocks have also attained maturity from Miocene to Pliocene times, and their thermal maturity ranges from gas generation to early maturity stage. The Oligocene source rocks also began to generate oil during the Miocene and are currently within the early-mature to mid-mature stage. The thermal maturity window for the Lower Miocene source rocks ranges from immature to early-mature stage. The present modeling results reveals that higher levels of thermal maturity are attained in areas with high geothermal gradients and heat flow values while the cooler areas exhibits lower levels of maturation. The onset of the oil window lies at 2859 m at A-1 (Central Swamp), 3240 m at B-2 (Coastal Swamp), 4732 m at B-1 (Coastal Swamp), and 4344 m at C-1 (Shallow Offshore). The depth to the onset of oil window is found deeper in the Shallow Offshore and western parts of the study area than in the eastern and northwestern parts. The result of this study suggest that the Paleocene, Eocene, Oligocene, and Lower Miocene source rocks are the principal source rocks for oil and gas generation in the Niger Delta Basin. [ABSTRACT FROM AUTHOR]

The Mannar Basin is a Late Jurassic - Neogene rift basin located in the Gulf of Mannar between India and Sri Lanka which developed during the break-up of Gondwana. Water depths in the Gulf of Mannar are up to about 3000 m. The stratigraphy is about 4 km thick in the north of the Mannar Basin and more than 6 km thick in the south. The occurrence of an active petroleum system in the basin was confirmed in 2011 by two natural gas discoveries following the drilling of the Dorado and Barracuda wells, located in the Sri Lankan part of the Gulf. However potential hydrocarbon source rocks have not been recorded by any of the wells so far drilled, and the petroleum system is poorly known. In this study, basin modelling techniques and measured vitrinite reflectance data were used to reconstruct the thermal and burial history of the northern part of the Mannar Basin along a 2D profile. Bottom-hole temperature measurements indicate that the present-day geothermal gradient in the northern Mannar Basin is around 24.4 oC/km. Optimised present-day heat flows in the northern part of the Mannar Basin are 30-40 mW/m2. The heat flow histories at the Pearl-1 and Dorado-North well locations were modelled using SIGMA-2D software, assuming similar patterns of heat flow history. Maximum heat flows at the end of rifting (Maastrichtian) were estimated to be about 68-71 mW/m2. Maturity modelling places the Jurassic and/or Lower Cretaceous interval in the oil and gas generation windows, and source rocks of this age therefore probably generated the thermogenic gas found at the Dorado and Barracuda wells. If the source rocks are organic-rich and oil- and gas-prone, they may have generated economic volumes of hydrocarbons. [ABSTRACT FROM AUTHOR]

The present work deals with the identification of the potential and generating capability of oil generation in the Jurassic source rocks in the Salam-3x well. This depending on the organo-geochemical analyses of cutting samples representative of Masajid, Khatatba and Ras Qattara formations, as well as, representative extract samples of the Khatatba and Ras Qattara formations. The geochemical analysis suggested the potential source intervals within the encountered rock units as follows: Masajid Formation bears mature source rocks and have poor to fair generating capability for generating gas (type III kerogen). Khatatba Formation bears mature source rock, and has poor to good generating capability for both oil and gas. Ras Qattara Formation constituting mature source rock has good to very good generating capability for both oil and gas. The burial history modeling shows that the Masajid Formation lies within oil and gas windows; Khatatba and Ras Qattara formations lie within the gas window. From the biomarker characteristics of source rocks it appears that the extract is genetically related as the majority of them were derived from marine organic matters sources (mainly algae) deposited under reducing environment and take the direction of increasing maturity and far away from the direction of biodegradation. Therefore, Masajid Formation is considered as effective source rocks for generating hydrocarbons, while Khatatba and Ras Qattara formations are the main source rocks for hydrocarbon accumulations in the Salam-3x well. [ABSTRACT FROM AUTHOR]

The timing of petroleum generation of source rocks is recognized to investigate the maturation level of the proven potential source formations for oil preservation dead lines, and predict the levels of thermal maturity of the studied sequences in terms of hydrocarbon generation and expulsion. For theses purposes four thermal burial history and maturity profiles were constructed of the Abu Gharaig-1 SW Umbaraka-1, GPZ-1, and GPX-1 wells. The results showed Abu Roash and Bahariya formations are immature to mature source rocks and have poor to fair potential to generate both oil and gas and still are within the early stage of hydrocarbon generation till the present time. Alam El Bueib and Masajid formations bear mature source rocks and have good generating capability for generating both oil and gas and entered the oil window since Cretaceous to Miocene times and lies within oil and gas windows at present time. Khatatba Formation bears a mature source rock and has good generating capability for both oil and gas and entered the oil window during Late Cretaceous to Eocene times. [ABSTRACT FROM PUBLISHER]

This study applied clumped isotope analyses to investigate how different limestone components (larger skeletal grains and enclosing matrix) and cements may have varying degrees of susceptibility to recrystallization during progressive burial. The results also provide new constraints on the temperatures of recrystallization and cementation, the nature of the waters involved, the timing of the diagenetic events, and the effect of oil emplacement on inhibiting diagenetic processes. We used clumped isotope measurements from core samples in two giant oilfields, together with petrography and well-constrained thermal histories, to study the reactivity of different limestone fabrics and whether the displacement of pore water by oil affected the recrystallization processes. We recognize seafloor micritization, cementation, and recrystallization as distinct diagenetic processes. The results indicate that skeletal grains record burial temperatures of 60 °C to72°C and enclosing coarse-blocky calcite cements record temperatures of 85 °C to 86 °C. Oxygen isotopes suggest that both processes involve high water/rock ratios. Burial histories together with carbonate Δ 47 values are used to estimate that the skeletal grains recrystallized from 99 to 70 Ma and the cements formed at around 54 Ma. By contrast, the matrix shows temperatures of 68 °C to 90 °C, consistent with continuous recrystallization at low water/rock ratios from 90 to 50 Ma. The large skeletal grains thus tend to recrystallize early, but are less reactive during subsequent burial because of larger crystal size, whereas the more finely crystalline and reactive matrix more faithfully records maximum burial conditions. The lower temperature recorded in the matrix relative to the present reservoir temperatures is interpreted as reflecting stoppage or inhibition of recrystallization by oil emplacement. • Co-located and coeval carbonate fabrics could recrystallize at different water/rock ratios • A crystal size impacts the mineral's proclivity towards recrystallization greater than the water/rock ratio aspect. • The finely crystalline and reactive matrix more faithfully records the maximum burial temperature than the skeletal grain • The Δ 47 record of the matrix reveals the stoppage of the dissolution-(re)precipitation reactions coincides with the timing of oil emplacement. • Our results extend the application of clumped isotope analyses to petroleum migration studies. [ABSTRACT FROM AUTHOR]

We possess rather little detailed information on the lives of the first inhabitants of Puerto Rico-the so-called "Archaic" or "Pre-Arawak" people-despite more than a century of archeological research. This is particularly true bioarchaeologically, as fewer than twenty burials of the several millennia of the Archaic Age have been recovered, let alone analyzed in any detail. Here, we present the results of archeological, osteological, radiometric, and isotopic analysis of five individuals from the Ortiz site in Cabo Rojo, southwestern Puerto Rico. Study of these previously unpublished remains, which represent a 20-25% increase in the sample size of remains attributed to the period, provides many critical insights into earliest Puerto Rican lifeways, including aspects of mortuary practice, paleodiet, and possibly even social organization. A review of their burial treatment finds a mostly standardized set of mortuary practices, a noteworthy finding given the site's potential millennium-long use as a mortuary space and the possibly distinct place(s) of origin of the individuals interred there. Although osteological analysis was limited by poor preservation, we were able to reconstruct aspects of the demography that indicate the presence of both male and female adults. Stable isotope analysis revealed dietary differences from later Ceramic Age individuals, while dental pathology indicated heavy masticatory wear attributable to diet and/or non-masticatory function. Perhaps most crucially, direct AMS dating of the remains confirms these as the oldest burials yet recovered from the island, providing us both with a glimpse into the lives of some of the island's first inhabitants, and with tantalizing clues to the existence of a different degree of cultural "complexity" than is often ascribed to these earliest peoples. The existence of what radiocarbon dates suggest may be a persistent formal cemetery space at the Ortiz site has potentially significant implications concerning the territoriality, mobility, and social organization of the earliest peoples of southwestern Puerto Rico., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Pestle et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

During the transition from Late Antiquity to the Middle Ages, the Roman Empire dissolved in the West and medieval empires were founded. There has been much discussion about the role that migration played in this transition. This is especially true for the formation of the Baiuvariian tribe and the founding of this tribal dukedom, which took place from the 5th to the 6th century in what is now Southern Bavaria (Germany). In this study, we aimed to determine the extent of immigration during the beginning of this transformation and to shed further light on its character. To achieve this goal, we analyzed stable isotope values of strontium, carbon, and nitrogen from the teeth and bones of over 150 human remains from Southern Germany, dating from around 500 AD. This group of individuals included women with cranial modifications (ACD) which can be found sporadically in the burial grounds of this period. Our results showed an above-average migration rate for both men and women in the second half of the 5th century. They also indicate that a foreign background may also be assumed for the women with ACD. The demonstrably different origins of the immigrants from isotopically diverse regions, and the identification of local differences in detectable migration rate, as well as indication for different timing of residential changes, highlight the complexity of immigration processes and the need for more studies at the regional level., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Velte et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)